The desire to lower costs and lighten, in the automobile equipment field, applies to all parts of this equipment.
This is in particular the case in the field of automobile locking means (switches, anti-theft devices, key operated caps, doors and bonnets).
Consequently, an object of the present invention is to provide a key which is both lighter, stronger and cheaper in respect of material and labor.
It is known that automobile lock keys have, as many other keys, a head facilitating the taking hold of and the actuation of the key (engagement, rotation, disengagement), which head follows on a peen or flat stem one or both edges of which stem are notched, the depth and the spacing between the notches varying from one key to the other so as to constitute a minimum protection against unauthorized opening of the lock.
These conventional keys are produced by blanking from a steel strip followed by a stamping of the head, a milling of grooves in the two faces parallel to the axis of the key whose characteristics differentiate the key entries of the lock. Thereafter, the teeth are produced by milling or cutting to variable depths. Keys exist whose stem profile is produced by stamping, the head of the key remaining flat. This system presents a difficult problem as concerns the connection of the flat part to the stamped part. The flat part does not resist the torque and such a key is much less attractive than a conventional key.
Moreover, in the case of a conventional key whose profile is produced by milling (costly operation) this key has a much lower strength than in the case where this profile is produced by stamping owing to the fact that the stamping surface hardens the material and does not destroy the fibers of the latter.